The Science

The technology behind ‘In Praise of Air’ turns clothing and textiles into a catalytic surface to purify air, which is much better than trying to find the best air purifiers. It was originally developed through another arts/science collaboration between artist and designer Professor Helen Storey and our Pro-Vice Chancellor for Science Tony Ryan. You can find out more about Catalytic Clothing


The key point underpinning Catalytic Clothing is that, when it comes to tackling pollution, it’s not enough to do it for yourself: one person will have a tiny effect, but if we all do it for each other then we could remove a lot of the air pollution in our towns and cities that’s put there by our cars, buses and industry.


Exposure to air-borne pollutants presents a risk to human health and also has a detrimental effect on ecosystems and vegetation. Air pollution is currently estimated to reduce the life expectancy of every person in the UK by an average of 7-8 months. The widespread introduction of Catalytic Clothing could dramatically reduce the level of air-borne pollutants, thereby improving the quality of life for all members

of society.


All major cities and towns have some form of air quality monitoring stations already in place. Those monitors record the levels of a range of major pollutants, such as NOx (nitrogen oxides) and VOCs (volatile organic compounds). Once Catalytic Clothing technology is in widespread use, considerable reductions in the levels of the pollutants could be observed using those monitors. Sheffield has poor air quality due, in part, to the topology of the city. We exceed the safe limits for nitric oxide, NOx,

in particular.


Catalytic Clothing harnesses the power of a photocatalyst to use sunshine and oxygen to break down air borne pollutants. A catalyst is a term used to describe something that makes a reaction proceed at a greater rate but isn’t actually consumed during that reaction. A photocatalyst gains the energy it needs to be active

from light.

When the light shines on the photocatalyst, the electrons in the material are rearranged and they become more reactive. These electrons are then able to react with the oxygen in the air and break it apart into 2 oxygen free radicals. A free radical is an extremely reactive molecule. These then react with water to make peroxide which oxidises the pollutants making harmless molecules that can be washed away. Photocatalysts have been incorporated into several commercially available products that possess de-polluting properties. These products include paints, cements and paving stones. But this is the world’s first pollution eating poem!


Photocatalyst particles of nano-TiO2 were sprayed on to the surface of the poem during manufacture. The size of the particles is important, the smaller they are the more surface is available for the reactions. Nanotechnology is an area of science that is concerned with the control and manipulation of matter on the molecular scale. This scale is often measured in nanometres, hence the nano in nanotechnology (see If you take an average 4 year old child with a height of 1m and then shrink them by a factor of 1000, they would then be the size of an ant (or a millimetre). If you shrink them again by a factor of 1000, they would be the size of a red blood cell (or a micrometre). We need to shrink them once more by a factor of 1000 to reach a scale measured in nanometres.


The coating only works in the presence of light and oxygen. It doesn’t need to be sunlight – the street lights which surround the catalytic poem will work too. Once ‘In Praise of Air’ is mounted on the side of the Alfred Denny Building, the photocatalyst will cause oxidation of any substances adsorbed on the surface. NOx will be converted to soluble nitrate and VOCs will be converted into fatty acids and soaps. 1 square meter of this coated fabric can take out about 2 g of NOx per day. So, our catalytic poem will remove the pollution from a bus or about 20 cars every day it is

in place.

In May 2014, the University of Sheffield will unveil the world’s first catalytic poem. 20 metres in height, the poem will be mounted on the wall of the Alfred Denny building on Western Bank. It is an original work by our Professor of Poetry, Simon Armitage, and the result of a collaboration with Pro-Vice Chancellor for Science, Professor Tony Ryan.


‘In Praise of Air’ was inspired by the University’s ongoing ambitions to bring an altruistic technology to people enabling them to clean-up air pollution as they walk around. The giant banner on which the poem is printed has been manufactured using revolutionary nano-technology. It is coated with a photocatalyst which eats pollution, enabling the poem to clean the air around it as it sits in place, overlooking the busy A57.

I write in praise of air.  I was six or five

when a conjurer opened my knotted fist

and I held in my palm the whole of the sky.

I’ve carried it with me ever since.


Let air be a major god, its being

and touch, its breast-milk always tilted

to the lips.  Both dragonfly and Boeing

dangle in its see-through nothingness…


Among the jumbled bric-a-brac I keep

a padlocked treasure-chest of empty space,

and on days when thoughts are fuddled with smog

or civilization crosses the street


with a white handkerchief over its mouth

and cars blow kisses to our lips from theirs

I turn the key, throw back the lid, breathe deep.

My first word, everyone’s  first word, was air.

The Project

In Praise of Air.

“There’s a legacy of poems in public places in Sheffield and on behalf of the University I wanted to be part of that dialogue, to show what we could do! I wanted to write a poem that was approachable, that might catch the attention of the passer-by and the wandering mind, and one that had some local relevance too. But I also hope it’s robust and intricate enough to sustain deeper enquiries - the English Department looks towards it for one thing, and I’d like to think it’s capable of getting the thumbs up or at least a nod from their direction, and from the big-brained students walking up and down Western Bank, and from discerning residents in the neighbourhood. I’ve enjoyed working with the scientists and the science, trying to weave the message into the words, wanting to collaborate both conceptually and with the physical manifestation of the work. Poetry often comes out of the intimate and the personal, so it’s strange to think of a piece in such an exposed place, written so large and so bold. I hope the spelling is right.”

Simon Armitage



In Praise
of Air Simon

The world's first catalytic poemdeveloped in collaboration withProfessor Tony Ryan at theUniversity of Sheffield

The Team









Simon is the University of Sheffield’s Professor of Poetry. He is one of the UK’s best known and most highly acclaimed poets. He has won multiple national and international awards for his poetry, prose, song-writing and documentary work and was awarded a CBE in 2010. Simon teaches on the MA in Creative Writing in the School of English and runs the Lyric festival with Joanna Gavins. He wrote ‘In Praise of Air’ specially for the catalytic poem project, inspired by his collaboration with scientists at the University.

Jo is a Reader in Literary Linguistics in the School of English at the University of Sheffield, where she teaches and researches literature and cognition. She has published widely on readers’ cognitive experiences of literary reading and she is particularly interested in how poetry is processed by the human mind. Jo also has a passion for making poetry accessible to the public and has run the Lyric festival with Simon Armitage each year since 2011. Jo is the Project Manager for the catalytic poem collaboration.

Tony is the Pro-Vice Chancellor for the Faculty of Science at the University of Sheffield. His research covers the synthesis, structure, processing and properties of polymers and he was in at the beginning of polymer nanotechnology. He has co-authored more than 200 papers and eight patents and written a book on polymer processing or how things are made from plastic. Tony presented the Royal Institution Christmas Lectures on Channel 4 in 2002 and is a regular contributor to TV, radio and newspapers. He was born in Leeds and got his three degrees from UMIST. He was made an OBE in 2006 for Services to Science.

David has been at the University 10 years this coming September, joining the Estates Department as a Quantity Surveyor from Chesterfield Borough Council. His early career started with Sheffield City Council in 1975 as an apprentice joiner before moving in to the role of Building Surveyor. He moved to Chesterfield BC in 1990 and completed his first degree in Quantity Surveying at Sheffield Hallam University. Moving to the University of Sheffield in 2004, he completed his Masters degree in Project Management shortly afterwards and increasingly took on a Project Management role.




The catalytic poem team

would also like to thank:

DED are a nose to tail creative agency with a hard-earned reputation for being innovative, adaptable, influential and extremely effective. Established in 1991, DED are a start-up that have been around for years. Designers for the catalytic poem project and rebrand of Lyric 2014.

Phil is the Manager of Project Sunshine at the University of Sheffield, a research programme that unites researchers from across the University as they seek solutions to the challenges of food and energy sustainability. Phil collaborated with Professors Tony Ryan and Helen Storey on the original Catalytic Clothing project and lent his invaluable expertise to the early development of the catalytic poem.


Mike Braddick (Professor of History and former Pro-Vice Chancellor of the Faculty of Arts and Humanities, University of Sheffield)

Iain Clasper-Cotte (Managing Director, Northern Flags)

Valerie Cotter (Director of Operations for the Faculty of Arts and Humanities, University of Sheffield)*

Philip Harvey (Registrar and Secretary and Chief Operating Officer, University of Sheffield)

Keith Lilley (Director of Estates and Facilities Management, University of Sheffield)


Cristal Chemicals (Kind suppliers of the product CristalACTIV™)


Without the support of each of these people, the catalytic poem project would not have been possible.


*In the beginning, it was all Valerie’s idea.







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